Polyalkylethyleneoxide pour point depressant additive



United States Patent 3,382,055 POLYALKYLETHYLENEOXIDE POUR POINTDEPRESSANT ADDITIVE Norman Jacobson and Herbert G. Burkard, Roselle,N.J., assignors to Esso Research and Engineering Company,

a corporation of Delaware No Drawing. Filed Feb. 24, 1965, Ser. No.435,031 2 Claims. (Cl. 44-62) ABSTRACT OF THE DISCLOSURE Polymers of1,2-epoxy alkanes having to 18 carbon atoms, wherein the molecularweight is in the range of 1,000 to 1,000,000 are pour depressants formiddle distillates and light lube oil stocks.

The present invention is broadly concerned with an additive forimproving the quality of middle distillates and light lube oil stocks.The present invention relates to improving the flow at low temperaturesand the pour characteristics of middle distillates and lube oil stocks.More particularly, the present invention relates to the manufacture ofimproved pour depressants for use with these middle distillates, inparticular, heating oils and diesel fuels, kerosene, aviation turbojetfuels, and other fuels and lubricating oils that are subject to lowtemperatures. The additives of the present invention are polymersderived from 1,2-epoxy alkanes.

With the increase in the use of hydrocarbon fuels of all kinds, aserious problem has arisen in areas frequently subjected to lowtemperatures with respect to the cold characteristics of these fuels.Particularly, serious problems have been encountered with heating oils,diesel oils and jet fuels that have too high a pour point, resultingeither in distributional or operating difficulties or both. For example,the distribution of heating oil by pumping or siphoning is rendereddifiicult or impossible at temperatures around or below the pour pointof the oil. Furthermore, the flow of the oil at such low temperaturesthrough the filters cannot be maintained, leading to the operatingfailure of the equipment.

Particularly the low temperature properties of petroleum distillatefuels boiling in the range between about 250 and about 750 F. haveattracted increased attention in recent years because of the growth ofmarkets of such fuels in subarctic areas and also because of thedevelopment of turbojet aircraft capable of operating at altitudes Wheretemperatures of 50 F. or lower may be encountered.

Thus it is one object of the present invention to provide heating oils,diesel fuel oils, kerosenes and jet fuels having low pour points.Aviation turbojet fuels in which the polymers of the present inventionmay be used normally boil between about 250 and about 550 F. and areused in both military and civilian aircraft. Such fuels are more fullydefined by US. Military Specifications MIL-F- 5624C, MILF-25554A,MIL-F-25558A, and amendments thereto. Kerosenes and heating oils willnormally have boiling ranges between about 300 and about 750 F. and aremore fully described in ASTM Specification D39648T and supplementsthereto, where they are referred to as No. 1 and No. 2 fuel oils. Dieselfuels in which the polymers may be employed are described in detail inASTM Specification D975T and later versions of the same specification.

The light lube oils with which the present invention is concerned arepetroleum neutral oils having viscosities in the range from 100 to 300Saybolt seconds at 100 F.

The polymeric pour depressants may, in accordance with the invention, beemployed in conjunction with a variety of other additives commonly usedin fuels such as those set forth above. Typical of such additives arerust inhibitors, anti-oxidants, dispersants, dyes, dye stabilizers, hazeinhibitors, antistatic agents and the: like. It will frequently be foundconvenient to prepare additive concentrates for use in the various typesof fuels and thus add all of the additives simultaneously.

In essence, the additives of the present invention consist essentiallyof polymers obtained from 1,2-epoxy alkanes. The molecular weights ofthe polymers are in the range from about 1,000 to 1,000,000, preferablyin the range from about 1,000 to 3,000 for heating oils and from 50,000to 150,000 for lube oils. The molecular weights are determined by K.Rasts method (Ber. 55, 1051, 3727 (1922)). The polymers are derived from1,2-epoxy alkanes and have a structural formula as follows:

wherein n is 8 to 16, preferably 10 to 14 and wherein x is 6 to 600,preferably 10 to 20. The epoxy compound EXAMPLE 1 A poly-1,2-epoxytetradecane was prepared as follows:

200 parts of l-tetradecene and 200 m1. of methylene chloride were addedto a 5 liter flask equipped with 'a stirrer, thermometer and condenser.m-Chloroperbenzoic acid (205 parts) pure) was dissolved in 1800 partsmethylene chloride and gradually added to the olefin solution at such arate that the reaction temperature did not.

rise above 40 C. After completion of the addition, the reaction solutionwas stirred overnight (16 hrs). The reaction solution gave a negativetest with starch-iodide paper and was filtered to remove them-chlorobenzoic acid. The reaction solution was Washed with 5% sodiumbicarbonate solution and then with water. The methylene chloride wasnitrogen stripped overnight at room temperature and the residualliquiddistilled. The portion boiling at 122 to 124 C./3.0 mm. was collected.The product 1,2-epoxy tetradecane (94.1 parts) was obtained as acolorless liquid.

The monomer, 1,2-epoxy tetradecane, is then polymerized utilizing acatalyst such as boron trifluoride-etherate to obtain low molecularweight product in the range from about 2,000 to 10,000. A diluent may ormay not be used and the catalyst may be suspended or dissolved in thediluent. The reaction proceeds at a temperature in the range from about70 to 50 0., preferably at about 8 C. for a period of about 1 to 4hours, such as about 2 hours.

High molecular Weight products in the range from about 10,000 to 100,000are obtained by the use of a coordinated anionic catalyst such asdiethyl zinc-water or triethyl aluminum-water. An inert diluent such aspentane,

3 hexane, benzene, xylene, etc., may be used. This reaction can beconveniently run at a temperature in the range from about to 150 C.(depending on the diluent used); preferably at about 70 C.

Other polymers were prepared using the following epoxy alkanes: C C Cand C -C using the technique described.

EXAMPLE 2 Approximately 16 parts monomer (1,2 epoxy tetradecane) werepolymerized in 12.5 parts pentane by the gradual addition of 1 ml. BF-etherate suspended in 3.2 parts pentane. The reaction was run at 8 C.for a period of 1 hour and then gradually allowed to warm to roomtemperature. Additional pentane (30 parts) was added to the reactionmixture and the organic phase was washed several times with water. Itwas next dried over anhydrous sodium sulfate and filtered. The pentanewas removed by nitrogen stripping and the residue placed in a vacuumoven at 60 C./ 125 mm. Hg. The crude residue was dialyzed to obtain apure product.

EXAMPLE 3 Approximately 16 parts monomer (1,2 epoxy tetradecane) werepolymerized without a diluent by the gradual addition of 1 ml. BF-etherate in 3.2 parts pentane. The reaction was run at 8 C. for aperiod of 2 hours. Pentane (75 parts) was added and the product wasobtained according to the procedure described in Example 2.

EXAMPLE 4 Following the procedure described in Example 3, a mixture of8.3 parts 1,2 epoxy dodecane and 8.3 parts 1,2 epoxy tetradecane werepolymerized by the gradual addition of 1 ml. BF -etherate dissolved in3.6 parts ethyl ether. The reaction was run at 8 C. for 2 hours. A crudeyield of 16.3 parts residue was obtained.

EXAMPLE 5 Following the procedure described in Example 3, approximately16 parts of a commercially available mixture of terminal epoxidecomposition 1,2 epoxy undecane, 1,2 epoxy dodecane and 1,2 epoxytridecane were polymerized yielding 8.1 parts of a crude polymericproduct.

EXAMPLE 6 Following the procedure described in Example 3, approximately17 parts of a mixture of 1,2 epoxy hexadecane (40%) and 1,2 epoxyoctadecane were polymerized at 13 C. by the gradual addition of 1 ml. BF-etherate suspended in 3.2 parts pentane giving 9.6 parts of a crudeproduct which was a semi-solid.

EXAMPLE 7 A liquid mixture of 44 parts benzene, 12.4 parts 1,2- epoxydodecane and 0.05 part Water was prepared in a screw cap bottle equippedwith a Teflon coated magnetic stirring bar. While the mixture wasstirred, 0.74 part diethyl zinc was added (as a 3 in. solution inbenzene). The operations were conducted in a nitrogen dry box. Thebottle was capped and transferred to a constant temperature bath at 50C. for 24 hours. The reaction mixture was dissolved in 2 liters ofbenzene, washed first with 1 liter of water containing 10 ml. 12 Nhydrochloride acid, then with an additional liter of water. The solutionwas dried over anhydrous sodium sulfate and filtered. The benzene wasremoved by nitrogen stripping at 75 to 85 C. The resulting polymer wasdried in a vacuum oven and the product yield was 10.9 parts.

4 EXAMPLE 8 Following the procedure of Example 7, a mixture of 44 partsof benzene, 12.4 parts 1,2 epoxy dodecane and 0.69 part triethylaluminum was reacted at 70 C. for 24 hours. The product recoverytechnique of Example 7 was used to give 11.1 parts of polymer having anintrinsic viscosity of 0.83 in toluene at 20 C.

EXAMPLE 9 Following the procedure of Example 7, a mixture of 44 parts ofbenzene, 12.4 parts 1,2 epoxy dodecane, 0.05 part water and 2.34 partsof trioctyl aluminum was reacted at 70 C. for 24 hours. The productrecovery technique of Example 7 gave a yield of 11.2 parts polymer whichhad an intrinsic viscosity of 0.21 in toluene at 20 C.

EXAMPLE 10 Following the procedure of Example 7, a mixture of 44 partsof benzene, 12.4 parts of 1,2 epoxy dodecane, 0.05 part water and 1.07parts triisobutyl aluminum was reacted at 70 C. for 24 hours. Theproduct recovery technique of Example 7 gave a yield of 11.4 partspolymer having an intrinsic viscosity of 0.91 in toluene at 20 C.

EXAMPLE 11 Following the procedure of Example 7, a mixture ofapproximately 12.5 parts G -C olefin oxide (a mixture of mainly terminalepoxides C H O where 11:11 to 15), 44 parts benzene, 0.05 part water and1.07 parts triisobutyl aluminum was reacted at 70 C. for 24 hours. Inattempting to dissolve the reaction mixture into benzene, a good portionof the product was found to be insoluble. The benzene suspension wasfiltered and 705 parts of polymer (insoluble in oil and benzene) wasobtained. The filtrate was treated according to the product recoverytechnique described in Example 7 and 3.55 parts (oil and benzenesoluble) polymer were obtained.

The polymers of Examples 2 to 11 were tested as pour point depressantsin a fuel oil and in a light lube oil. The results are shown in Tables Iand II.

Table I.--Pour point data on polymers in fuel oil Fuel oil wasapproximately 50/50 v01. percent straight run and cracked stocks from amix-ture of Venezuela and Gulf Coast erudes. The following are typicalspecificat ons:

Cloud point 4 Pour point --5 Aniline p'oint 132 Viscosity SUS/l00 F 34.2API gravity 33.0 Density g./60 IL- 0.860

Table II.--Pour point data on polymers in Mineral oil Pour point (F.)Mineral oil 1 15 Oii+0.1 wt. percent polymer of Example A solventrefined neutral mineral lubricating oil having a viscosity of 169.3 SUSat F.

What is claimed is:

1. A distillate fuel oil boiling between about 250 F. and 750 F.improved in pour point by the incorporation therein of a pour depressingefiective amount within the range from about .005 to .2% by Weight of anoil soluble 5 polymer having a structural formula as follows:

|:$H-GHr- GnHZnH 0 wherein n is 8 to 16 and x is from 6 to 600.

References Cited UNITED STATES PATENTS SWern et a1. 252-52A Lieber eta1. 44-62 X Butler 25252 Stayner et a1. 44-62 X Bailey 260-6l5 2. Acomposition as defined by claim 1, wherein n 10 DANIEL WYMAN PflmaryExaminer W. J. SHINE, Assistant Examiner.

is 10 to 14, x is 10 to 20, and said polymer has a Rast molecular weightof about 1,000 to 3,000.

"Patent No. 3,382,055

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION May 7, 1968 NormanJacobson et a1.

It is certified that error appears in the above identified patent andthat said Letters Patent are hereby corrected as shown below: Column 5lines 7 and 8, the formula should appear as shown below:

-CHCH 'O Signed and sealed this 16th day of December 1969.

fittest:

Edward M. Fletcher, Jr.

Attesting Offi e Commissioner of Patents WILLIAM E. SCHUYLER, JR.

